JP2014016465A5

JP2014016465A5 -

Info

Publication number: JP2014016465A5
Application number: JP2012153685A
Authority: JP
Filing date: 2012-07-09
Publication date: 2015-08-20
Anticipated expiration: 2032-07-09

Description

また、フォーカシングの際の収差変動を改善するために、複数のレンズ群を光軸方向に移動させるフローティング方式が知られている（特許文献２）。また、マクロ機構を有するズームレンズが知られている（特許文献３）。特許文献３のズームレンズでは、望遠端において、第１レンズ群と第２レンズ群の間隔が増大するように第１レンズ群と第２レンズ群を移動させることにより、マクロ撮影を可能としている。 Also, a floating method is known in which a plurality of lens groups are moved in the optical axis direction in order to improve aberration fluctuations during focusing (Patent Document 2). A zoom lens having a macro mechanism is also known (Patent Document 3). In the zoom lens of Patent Document 3, macro photography is enabled by moving the first lens group and the second lens group so that the distance between the first lens group and the second lens group is increased at the telephoto end.

本発明のズームレンズは、物体側から像側へ順に、正の屈折力が最も強いレンズ群Ｌｐ、負の屈折力のレンズ群Ｌｎ、正の屈折力のレンズ群Ｌｐ２を有し、ズーミングに際して隣り合うレンズ群の間隔が変化するズームレンズであって、
無限遠から所定の有限距離までのフォーカシングとズーミングが可能な第１領域においては、ズーミングに際して２以上のレンズ群が移動し、フォーカシングに際して少なくとも１つのレンズ群が移動し、
望遠端から前記所定の有限距離より短い物体距離へのフォーカシングが可能な第２領域においては、２以上のレンズ群が移動することにより望遠端から最至近の物体距離へのフォーカシングが行われ、最至近の物体距離に合焦している状態をマクロ端として、
広角端に比べてマクロ端において、前記レンズ群Ｌｐが物体側に位置し、前記レンズ群Ｌｐと前記レンズ群Ｌｎの間隔が大きくなり、前記レンズ群Ｌｎと前記レンズ群Ｌｐ２の間隔が小さくなることを特徴としている。 The zoom lens according to the present invention includes, in order from the object side to the image side, a lens group Lp having the strongest positive refractive power, a lens group Ln having a negative refractive power, and a lens group Lp2 having a positive refractive power. A zoom lens in which the interval between the matching lens groups changes ,
In the first region where focusing and zooming from infinity to a predetermined finite distance are possible, two or more lens groups move during zooming, and at least one lens group moves during focusing.
In the second region in which focusing from the telephoto end to an object distance shorter than the predetermined finite distance is performed, focusing from the telephoto end to the nearest object distance is performed by moving two or more lens groups. When focusing on the closest object distance as a macro edge,
The lens group Lp is positioned on the object side at the macro end compared to the wide-angle end, the distance between the lens group Lp and the lens group Ln is increased, and the distance between the lens group Ln and the lens group Lp2 is decreased. It is characterized by.

無限遠（無限遠物体）から有限距離（第１の物体距離）まで合焦（フォーカシング）可能な距離範囲を第１領域とする。第１領域の有限距離から更に近い至近距離（最至近距離）まで合焦可能な距離範囲を第２領域とする。第１領域ではフォーカシング駆動機構とズーム駆動機構によってフォーカシング及びズーミングが行われる。尚、第１領域の望遠端又は広角端から２以上のレンズ群が移動することにより、第１領域から第２領域へ移行する。 A distance range in which focusing can be performed from infinity (an object at infinity) to a finite distance (a first object distance) is defined as a first region. A distance range that can be focused from the finite distance of the first region to the closest distance (closest distance) is defined as the second region. In the first region, focusing and zooming are performed by the focusing drive mechanism and the zoom drive mechanism. Note that, when two or more lens groups move from the telephoto end or wide-angle end of the first region, the first region shifts to the second region.

Claims

In order from the object side to the image side, there are a lens unit Lp with the strongest positive refractive power, a lens unit Ln with a negative refractive power, and a lens unit Lp2 with a positive refractive power, and the distance between adjacent lens units changes during zooming. A zoom lens that
In the first region where focusing and zooming from infinity to a predetermined finite distance are possible, two or more lens groups move during zooming, and at least one lens group moves during focusing.
In the second region in which focusing from the telephoto end to an object distance shorter than the predetermined finite distance is performed, focusing from the telephoto end to the nearest object distance is performed by moving two or more lens groups. When focusing on the closest object distance as a macro edge,
The lens group Lp is positioned on the object side at the macro end compared to the wide-angle end, the distance between the lens group Lp and the lens group Ln is increased, and the distance between the lens group Ln and the lens group Lp2 is decreased. Zoom lens characterized by.

2. The zoom lens according to claim 1, wherein a lens group that moves during focusing of the first region moves during focusing of the second region .

When the focal length of the lens unit Lp is F _Lp and the focal length of the lens unit Lp2 is F _Lp2 ,
0.05 <F _Lp / F _Lp2 <0.60
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.

When the focal length of the lens unit Ln is F _Ln and the focal length of the lens unit Lp is F _Lp ,
0.20 <F _Lp / | F _Ln | <0.90
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.

The distance on the optical axis from the object-side lens surface of the lens unit Lp to the front principal point position of the partial system from the lens unit Lp to the lens unit Lp2 at the macro end of the second region is o1LP, When the distance on the optical axis from the object side lens surface of the lens unit Lp to the image side lens surface of the lens unit Lp2 at the macro end of the second region is BldLP
−0.30 <o1LP / BldLP <0.40
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.

When the amount of movement of the lens unit Lp when changing from the telephoto end to the macro end is mLp, the total lens length at the wide angle end is TLDw, and the imaging magnification when focusing on an object at the closest distance at the macro end is βm,
0.01 <(mLp / TLDw) / βm <0.40
The zoom lens according to claim 1, wherein the following conditional expression is satisfied.

In order from the object side to the image side, a first lens group having a positive refractive power and a second lens group having a negative refractive power are provided separately from the sub-system from the lens group Lp to the lens group Lp2, and at a wide angle end. 7. The zoom lens according to claim 1, wherein a distance between the first lens group and the second lens group is larger at a telephoto end than at a zoom lens.

Upon driving from the telephoto end to the macro end, the zoom lens according to claim 7 in which the first lens group is thus being moved toward the image side.

Most zoom lens according to any one of claims 1 to 6 a first lens unit having a negative refractive power on the object side, characterized in that it is placed.

10. The zoom lens according to claim 1, wherein the lens group that moves during focusing of the first region is a lens group having the strongest negative refractive power.

When focusing on an object at infinity at Nozomu far end, a position in the optical axis direction of the lens unit which moves during focusing, the position of the optical axis of the lens group adjacent to the image side of the lens group, the third The zoom lens according to claim 10, wherein the zoom lens overlaps in a part of the two regions.

The lens Lp and the lens group Lp2 is a zoom lens according to any one of claims 1 to 11, characterized in that moving at the same locus during zooming.

In the zoom lens, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens having a negative refractive power. lens group, the fifth lens unit having positive refractive power, a sixth lens unit having a negative refractive power, is composed of a seventh lens unit having positive refractive power, the lens units are moved during zooming, the fifth lens group 7 is the lens group Lp, the sixth lens group is the lens group Ln, and the seventh lens group is the lens group Lp2. lens.

In the zoom lens, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens having a positive refractive power. lens group, the fifth lens unit having a negative refractive power, is composed of a sixth lens unit having positive refractive power, the lens units are moved during zooming, the third lens group is the lens group Lp, the second The zoom lens according to claim 1 , wherein five lens groups are the lens group Ln, and the sixth lens group is the lens group Lp2 .

The zoom lens includes, in order from the object side to the image side, a first lens group having a negative refractive power, a second lens group having a positive refractive power, a third lens group having a negative refractive power, and a fourth lens having a positive refractive power. lens group, the fifth lens unit having a negative refractive power, is composed of a sixth lens unit having a positive refractive power, the lens units are moved during zooming, the first lens group is the lens group Lp, the second The zoom lens according to claim 1 , wherein five lens groups are the lens group Ln, and the sixth lens group is the lens group Lp2 .

In the zoom lens, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens having a negative refractive power. lens group is composed of a fifth lens unit having positive refractive power, the lens units are moved during zooming, the a third lens group wherein the lens group Lp, the fourth lens group be the lens unit Ln The zoom lens according to any one of claims 1 to 6 , wherein the fifth lens group is the lens group Lp2 .

An image pickup apparatus comprising: the zoom lens according to claim 1 ; and an image pickup element that receives an image formed by the zoom lens .